HOMEBREW Digest #2962 Wed 24 February 1999

FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
Digest Janitor: janitor@hbd.org
Many thanks to the Observer & Eccentric Newspapers of
Livonia, Michigan for sponsoring the Homebrew Digest.
URL: http://www.oeonline.comContents:oat malt report and recipes (Jeff Renner)re: grain bag lauter tuns ("Curt Abert")Re: oat malt report and recipes (Jeff Renner)Pump operation questions ("Dana H. Edgell")Two models of vacuum evaporation of alcohol ("S. Wesley")cleaning stainless (Alan McKay)Yeast from bottles (Petr Otahal)Re: Computer Controlled brewing (Joe Stone)Brewery Automation Web Article (Ken Schwartz)The Jethro Gump Report-Part 1 ("Rob Moline")The Jethro Gump Report-Part 2 ("Rob Moline")Philly Competition March 20, 1999 (birman)Automatic Mill, was Re: Motors for Malt Mill (Doug Roberts)This is gyle! (Alan McKay)small bottles? (John Herman)Milling Grains (Jack Schmidling)iodophor film (Paul Dey)Lautering Temperature ("Fred L. Johnson")Re: Fake decoction/ Weissheimer haze ? (Paul Shick)Re: Computer Controlled Brewing ("Peter J. Calinski")Corny Keg Thread Size/Type (chatgros)Drunk Monk Challenge - Second Notice!! ("Formanek, Joe")
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----------------------------------------------------------------------
Date: Mon, 22 Feb 1999 14:29:25 -0500
From: Jeff Renner <nerenner at umich.edu>
Subject: oat malt report and recipes
An update on this rare and overlooked ingredient:
My oat malt brown ale (1.051, 30 IBU, see recipe at end) has really come
into form at nine weeks now. The 11% malted oats really do make a
distinctive flavor and almost oily mouthfeel contribution, which is much
more evident in the midieval Domesday Ale (50% home malted oats, 24% malted
wheat, 24% malted barley, 2% chocolate, first runnings only, O.G. 1.096, no
hops, no bottle priming), now bottle aging for the millenium. The brown
ale took some time to clear and is still slightly hazy, probably because of
the beta glucans.
The Domesday Ale is still very hazy (probably home malted oats are worse
than commercial?), but in the 12th C, ale was drunk from opaque vessels, so
who cares. This ale is thick! About 10W40, I'd guess. Sweet, still, not
very complex this young, some diacetyl and caramel, chocolate and oat malt
aroma and flavor. We'll see how it is after a year in the bottle.
The only maltster I know of that malts oats is Thomas Fawcett and Sons
http://www.fawcett-maltsters.co.uk/welcom.htm . The importer for Fawcett
is Claude Bechard,
North Country Malt Supply, 12 Stewart St, PO Box 665, Rouses Point, NY,
12979, 518-297-2604 (yada, yada). I was very pleased with the quality of
this apparently unique malt, and wish I'd had it for the Domesday Ale.
Malted oats would seem to be an ideal ingredient for an English or Scottish
stout. Here the haze doesn't matter. The only commercial malted oat brew
I am aware of is Maclays Oat Malt Stout, which is available in the U.S.,
although I haven't tried it. (Arcadian of Battle Creek, MI has an oatmalt
stout, but it is made with flakes, and it is unclear to me after email
exchange with the English maltster that they are definitely malted. They
definitely are non-diastatic.)
Protz's _Real Ale Almanac_ has this about Maclay's: 1.045 OG, ABV 4.5%, 50
deg. color EBC [roughly 25L], 35 IBU. 70% Marris Otter pale ale malt, 22%
malted oats, 6% roast barley, 2% chocolate; Fuggles whole hops. He calls
it a "Luscious, silky stout based on an 1895 recipe."
I hope someone will try brewing this this winter (I have too many others
planned). I don't know what yeast Maclay's uses, but any of the more
characterful British ones would do well, I'd think. I like Strathcona (see
below).
Anyone who brews this please report back.
Here is the outline of the brown ale: For *7.75* gallons, 1/4 bbl:
Untreated temp. hard Michigan well water; 9 lbs. Paul's pale ale malt, 2
lbs. Durst Munich, 1.5 lbs. Fawcett oat malt, 0.75 lbs NW 60L crystal, 0.75
lb. Durst 90L crystal, 3 oz. Scotmalt chocolate; 2.0 oz. whole Cascade 5.0%
alpha for 65 minutes, 0.5 oz. homegrown Cascade 22 min., 0.4 oz. ditto 7
minutes, 0.5 oz. ditto at heat off (but with 10 minute settling steep); top
cropped repitched YCKC "Strathcona" yeast (NCYC 1332). I was cleaning out
the closet and don't think the malt brands are real important.
Jeff
-=-=-=-=-
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
"One never knows, do one?" Fats Waller, American Musician, 1904-1943.
Return to table of contents
Date: Mon, 22 Feb 1999 14:17:32 -0600
From: "Curt Abert" <abert at flanders.isgs.uiuc.edu>
Subject: re: grain bag lauter tuns
In HBD #2959, Frank asks about people's experiences with grain bags
lauter tuns:
> I would like to hear from the others in this group on their experiences
> using a filter bag in the sparge bucket. What do they see as drawbacks or
> negative impacts on the beer.
I had used this technique for 2 years. It was very easy (and cheap) to
set up, but this last fall I made myself a slotted copper manifold instead.
I don't think I ever saw any negative impacts from this meathod on the
final product, but there were some drawbacks, namely:
- loss of extract (probably due to channeling),
- excessive vorlauf (often up to a 1.3 gallons needed to be recirculated)
- difficult clean up (getting all of the grain out of the bag is was a chore).
With my manifold, I only need to recirculate around a quart of wort
before it runs clear, my extraction rates increased (on average 5 pts/lb/gal),
and clean up is *way* easier.
Just my 2 cents...
Curt Abert
Champaign, IL
abert at isgs.uiuc.edu
Return to table of contents
Date: Mon, 22 Feb 1999 15:22:06 -0500
From: Jeff Renner <nerenner at umich.edu>
Subject: Re: oat malt report and recipes
More oat malt information from an email to me last year from the maltster
(isn't it nice that there is still a family member involved in this old
firm?):
3) Oat malt laboratory worts are normally slightly hazy rather than clear.
Oats are not normally low in protein and are quite difficult to modify from
a protein viewpoint, which could well explain this. Our current stock
gives values of 11.8 % total protein with an index of modification of
27.8%. 4) As far as mash schedules are concerned we would suggest you
ensure temperatures are between 63 degrees C and 68 degrees C during
mashing in with a one hour minimum stand after mashing in a grist composed
of 50% oat malt and 50% lager malt. 5) You should aim at a liquor/grist
ratio of between 2.5:1and 3:1. 6) Oat malt needs very close mill
settings to achieve an acceptable grist. For normal malts our standard
mill setting is 62 thou top and 58 thou bottom- for oat malt we
drastically reduce these settings to 48 thou top and 42 thou bottom.
Certainly a point to watch to produce an optimal grist for mashing. I
hope some of all this is useful. We are delighted that you are using our
malts and hope that you have every success with your future brews. Yours
sincerely James Fawcett
-=-=-=-=-
Jeff Renner in Ann Arbor, Michigan c/o nerenner at umich.edu
"One never knows, do one?" Fats Waller, American Musician, 1904-1943.
Return to table of contents
Date: Mon, 22 Feb 1999 15:52:42 -0800 (PST)
From: "Dana H. Edgell" <edgell at cari.net>
Subject: Pump operation questions
Dear HBD,
I have a couple of questions for pump/electrical/RIMS crowd so if you're
not interested please page down.
1) I have noticed that some heat exchange RIMS designs on the web include a
valve to bypass the HE coil when heating isn't required. Why not simply
turn the pump off? Recycling only during heating sould be enough for the
desired clarity shouldn't it? Does turning the pump on and off infrequently
somehow affect the grian bed compactions?
2) I have 120VAC to 24VDC plug in adapter and a 24V relay (NOT solid state)
to control my pump. Do I need some sort of resitor to control the current
in this circuit and prevent overheating?
3) I saw a speed controller for an overhead fan motor in the hardware store
the other day and it got me thinking. Is there any advantage to electronic
speed control of the pump motor vs a downstream valve to control the flow
rate.
Thanks in Advance,
Dana
- ------------------------------------------------------------------
Dana Edgell edgell at cari.net
2939 Cowley Way #G http://www.quantum-net.com/edge_ale
San Diego, CA 92117 (619) 276-7644
Return to table of contents
Date: Mon, 22 Feb 1999 19:26:25 -0500
From: "S. Wesley" <WESLEY at MAINE.MAINE.EDU>
Subject: Two models of vacuum evaporation of alcohol
Dear "AJ",
I agree with your reformulation of my spreadsheet calculations
in terms of molar fraction instead of mass fraction for an evaporation
limited system. I get essentially the same result as you for the
quantity of water that must be removed in this model. I am
becoming convinced, however, that this model is not valid for the
conditions under which I am evaporating. Ironically, using cheap
equipment saves me.
There are two extreme cases for this process which I will refer
to as evaporation limited and quasi-static. In the evaporation limited
model you have a vacuum pump which instantly removes all gasses
as they evaporate resulting in molar evaporation rates which are
proportional to the molar fraction.
To understand the quasi-static model consider the following
setup. Two beakers containing ethanol and water are placed in a
bell jar which is completely evacuated at 19C. After some time
the partial pressure of water will be 16.477 mm and the partial
pressure of ethanol will be 40mm. (Numbers from CRC Handbook)
2.4 times as many moles of ethanol will evaporate as water, and
since ethanol has a molecular weight of 46 and water 18 this means
that 6.13 times as much ethanol by mass will evaporate. Once
equilibrium is achieved the system is completely evacuated again
and the process repeats until all the ethanol is gone. In the end you
will evaporate 6.13 times more ethanol by weight than water.
In reality what is hapening here is we are pumping so slowly that
we never move the system away from equilibrium.
I am using an aspirator which has a nominal ultimate pressure
of 36 mm and a pumping speed of 1.4 litres per min. At 28C, where
I am working, the partial pressure of water is about 28 mm and
ethanol is about 67 mm. total pressure of 95 mm. I am pumping
out 35 ml of a 350 ml sample in 20min. If I assume I am pumping
out mostly water vapor, it means I am removing roughly 2 mol of
water. 44.8 liters at STP from a pump which can't deliver that in 20
min. I am essentially flooding the pump because I can evaporate
more quickly than I can pump. This means that I am close to the
quasi-static model and most of what I evaporate is actually
alcohol at first. If this is a valid approach to the problem then it
is not necessary to evaporate 60% of the volume, in fact the
10% I did is overkill. This is corroborated (by no means
conculsively) by the complete lack of phisiological reaction I
experienced from drinking, over the course of an hour, five
bottles of beer treated this way.
On the other hand if the evaporation limited model is valid
the last thing you want to do is use a reflux column. This is
counterpoductive as it reduces the molar fraction of alcohol in the
wash making it harder to evaporate alcohol. It is much more
effiicient to remove evaporated water once and replace it when you
reach your target concentration of alcohol, than to evaporate it
many times and dilute the alcohol molar fraction into the bargain.
As you suggested I got my hands on a spectrophotometer.
It is a Spectronic 20 built by Milton Roy Company. I haven't
had time to RTFM yet, but I don't think they have a chapter on
analyzing alcohol content in beer. Any further insight into this
process would be greatly appreciated.
Best Wishes,
Simon Andrew Wesley
Return to table of contents
Date: Mon, 22 Feb 1999 20:52:58 -0500
From: Alan McKay <amckay at ottawa.com>
Subject: cleaning stainless
In 2960 Matthew Birchfield asks about cleaning stainless.
There are all kinds of products maide from the same stuff
as "Barkeeper's Friend". Here you get it in any hardware store.
Just ask for stuff for cleaning stainless. It's a white powder,
and there really is nothing better (or even anything that comes
close) for cleaning stainless or copper.
I find best results when you use a single drop of quality
disk detergent with it (like the yellow ivory, or Dawn), and
then just enough water to work up a paste.
Rinse extremely well!
cheers,
-Alan
- --
"Brewers make wort, yeast makes beer"
- Dave Miller's Homebrewing Guide
http://www.magma.ca/~bodnsatz/brew/tips/Return to table of contents
Date: Tue, 23 Feb 1999 13:30:43 +1100
From: Petr Otahal <potahal at postoffice.utas.edu.au>
Subject: Yeast from bottles
This may sound like an uneducated stupid question but I have been reading a
lot about yeast culturing and storing on the web and such.
Why doesnt everyone just restart their yeast from their own home brew
bottles by building up from the sediment in the bottle? Isnt this a lot
less complicated than having to use agar and stuff? Surely you could do
this at least a few times without getting many mutations and the like.
Thanks for any replies
Pete
Return to table of contents
Date: Mon, 22 Feb 1999 18:22:41 -0800
From: Joe Stone <joestone at cisco.com>
Subject: Re: Computer Controlled brewing
Shane,
> Has anyone created an interface to actually control boil/mash temps
with a
> computer? Or even logging your brew session or fermentation with your
> computer (having it automatically record the temp at certain
intervals).
> I've had some experience talking through serial ports with Perl, and
have
> programmed in Java, C, C++... as well. Unfortunately, I don't have the
$$
> for digital thermometers - can anyone point me to a cheap one? In any
case,
> I'm interested!
You can see my computer-controlled brewing system at,
http://www.employees.org/~joestone/Sbs/
The brewing system is controlled by an IBM PC-AT (80286) with an ADIO
(Analog / Digital, Input / Output) board. I use a "float" level
indicator to measure the level of water in the sparge vessel and a float
switch to monitor the level of water/wort above the grain bed in the
mash vessel. I use one pump to transfer dough-in and sparge water from
the sparge vessel to the mash vessel and a second pump to recirculate
wort to the mash vessel. I use an electric water heater element (in
conjunction with a National Semiconductor LM34 temperature sensor) in
the sparge vessel to increase and maintain the temperature of sparge and
dough-in water. I use a Morris style RIMS tube and electric heater
element (in conjunction with a LM34 temperature sensor) to increase and
maintain the temperature of the mash. I use four solenoid valves to
control the flow of water/wort. I use a pressure transducer to monitor
the level of wort within the boil vessel. The pumps, solenoid valves
and electric water heater elements are controlled using the ADIO board
via SSRs (solid state relays).
The state of the entire system,
sparge target temperature
sparge actual temperature
mash target temperature
mash actual temperature
sparge target water level
sparge actual water level
sparge heater element
mash heater element
sparge pump
mash pump
sparge propane stove
boil propane stove
sparge water solenoid valve
mash-to-boil wort solenoid valve
boil-to-chiller wort solenoid valve
chiller water solenoid valve
is logged to a batch file once every minute.
I am extremely happy with this computer-controlled approach to brewing.
Check out the website. If you still have questions, feel free to send
me E-mail.
Joe
Return to table of contents
Date: Mon, 22 Feb 1999 19:36:16 -0700
From: Ken Schwartz <kenbob at elp.rr.com>
Subject: Brewery Automation Web Article
It's not often that a parade of beer bottles crosses my desk at work,
but that's exactly what happenned today. Among the many trade rags I
get is Product Design & Development, and the latest issue has a feature
article on automation at the Spoetzl ("Shiner Bock") Brewery. You can
check it out on-line at http://www.pddnet.com/dtopics/0299f1.htm .
- --
*****
Ken Schwartz
El Paso, TX
Brewing Web Page: http://home.elp.rr.com/brewbeer
E-mail: kenbob at elp.rr.com
Return to table of contents
Date: Mon, 22 Feb 1999 21:11:34 -0600
From: "Rob Moline" <brewer at isunet.net>
Subject: The Jethro Gump Report-Part 1
The Jethro Gump Report-Part 1
After the 3 part 1984 "Applied Environmental Microbiology" article, Sept
84, American Society for Microbiology by Casey, Magnus, Ingledew..."High
Gravity Brewing: Effects of Nutrition on Yeast Composition, Fermentative
Ability, and Alcohol Production.".....
I received many interesting comments....selected two to forward to Mr.Cone,
and have had them answered briefly......The Questions and responses
follow.....If they don't follow a direct Q&A style, forgive me..this is
really just the product of 3 personal e-mails......
I trust it meets your interests.....
Rod Prather Asks
<SNIP>
>Did the paper give any insight as to why sake ferments to 20%. I have been
>told of a phenomena called accomodation where the alcohol tolerance
>increases if sugars are added slowly as fermentation progresses. Sake
>emmulates this because the koji, or aspergillus fungus, that produces the
>sugars continues working after the yeast is added to the rice liquor so
>conversion and fermetation takes place simultaneously. I have wondered if
>the principle could be applied to high alcohol beers.
Steve Alexander writes....
><SNIP>
>3/ My synopsis/comments follow - could you fill in some of the details as
>you
> understand them ... especially figure 5 since this might be of
> considerable practical value to HB high gravity brewers.
>4/ Reference 22 is ???
>5/ Did the paper give results for Sterol/UFA/FAN additions alone and in
>various combinations. If so which appear to be most effective ? I get the
>impression that added sterol isn't the issue, but FAN (what levels?) and
>certain unsaturated FA's are.
>===
>
>Brewing yeast can fully ferment high gravity wort with proper nutrition and
>reach 16.2% alc at 14C/57F, high yeast viability, normal brewing periods.
>Wort must contain nitrogen supplements (yeast extract, FAN) and either
>sterol(ergosterol) + UFA(oleic fraction of TWEEN80) supplements.
>Fermentation then proceeds rapidly DUE TO INCREASED YEAST GROWTH, [not
>increased alcohol tolerance].
>
>O2 deficiencies can be overcome by either the addition of 24 ppm ergosterol
>with 0.24% (vol/vol) Tween 80 as a source of oleic acid OR by periods of
>oxygenation during the fermentation.
>
>[Both of these methods have potentially serious negative flavor/head
>consequences for beer. Chronic human sterol intake around 1mg/day (~1.5
>fl.oz at 24ppm) can result in hypercalcemia with CNS consequences - so
>don't
>try this at home !]
>
>High gravity worts had insufficient FAN. Levels of yeast extract
>nitrogen)
>required c>an be drastically reduced by the use of an all malt base.(Fig
>5).
>[Rob - can> you tell us what is in fig 5 ? This should indicate how much
>yeast extract is needed when brewing barleywines - no ?]
>
>Tolerance to the effects of ethanol on generation time, viability, and
>solute uptake are enhanced when C18:2 UFA [linoleic acid], rather than
>C18:1
>[oleic acid] was added.
>
>[C18:1(oleic acid), C18:2(linoleic) have 18 carbons, one and two degrees of
>unsaturation resp'y. The unsaturated bond synthesis requires oxygen. The
>statement above says than linoleic protects yeast from the negatives of
>ethanol. Is linoleic+FAN the key to high gravity ferments ?]
>
>The early rise and then continued decline in fermentative power values has
>been attributed to an increase in the cellular levels of hexokinase
>activity
>by the buildup of intracellular ethanol levels with time(27).
>
>[hexokinase is an enzyme that starts off the fermentation process by
>converting various hexose sugars into their hexose-6-phosphate form.
>ATP(energy) and Magnesium ions are required. The phosphated sugars have an
>inhibitory effect on the enzyme(regulation). What is the impact of ethanol
>on this step ?]
>
>>Yeast glycogen and sterols were found to differ considerably between
>anaerobic and semi-anaerobic conditions and on the nutritional supplement
>used.
>
>Glycogen - < 10% semi-anaerobic, unsupplemented or supplemented
> ~30% anaerobic fermentations [no supplement ??]
> 10.5% anaerobic, fully supplemented (fastest ferment)
>Sterol - 0.85-1.09% semi-anaerobic [w/o-with supplement?]
> 0.27-0.56% anaerobic [w/o-with supplement?]
>
>Sterols were not the limit of growth. [!!] [Or else sterol >0.2% is
>required for high gravity/high ethanol growth. Glycogen is an energy
>storage carbohydrate, so high levels result from non-carbohydrate growth
>limits (the energy would be used to grow if possible).]
>==
>
>The addition of sterol *appears* to be unnecessary. Among the UFAs linoleic
>is most effective than oleic. Will oleic+FAN do the trick ?
>
>I still have doubts that UFA additions or mid-fermentation oxygenation will
>make a tasty beer, but this should add some weight to the idea of
>repitching
>healthy well aerated starters with FAN additions.
>Steve
End of Questions.....Response to follow in Part 2
Jethro
Return to table of contents
Date: Mon, 22 Feb 1999 21:14:40 -0600
From: "Rob Moline" <brewer at isunet.net>
Subject: The Jethro Gump Report-Part 2
The Jethro Gump Report-Part 2
Response Follows.....
Rob,
Just as a starter. Several breweries world wide are commercially producing
hi gravity beer. So, many of the problems (flavor) that were originally
associated with this new technology have been worked out. Most of the
problems were solved by the adequate use of oxygen and supplying the yeast
with enough nitrogen both in the amino acid form and Ammonium phosphate.
Mike Ingledew has produced 16.8% alcohol beer. He has reached over 21%
alcohol for other industrial beverages.
Labatt, Molson & Guiness have produced 18 - 20% alcohol beers.
Guiness Book of Records is 23% alcohol beer.
Uncle Igors Famous Fall Water Brewhouse, Scotland produced 23.3% alcohol
beer.
Clayton Cone produced 21% Alcohol beer.
There has to be a holistic approach to all fermentations especially higher
alcohol fermentations.
Fermentable nitrogen is a key factor. Wort is often lacking in enough FAN
for even low gravity fermentation because of the nature of the original
malted barley. If it is underdeveloped there will be less available
nitrogen. Single step mashing can result in low FAN. Boiling the wort
causes some of the FAN to bind with the reducing sugars (glucose & fructose)
making them unavailable for the yeast. There will be lots of protein that
humans can digest, however, yeast will not be able to assimilate. Malt
extract can have the same problem.
Beer yeast can use Ammonia as the sole source of nitrogen. However they
prefer a balanced diet of amino acids and NH3. Fermaid K offers this
balanced diet plus essential minerals (magnesium).) and vitamins. It is very
common for commercial breweries to add yeast nutrients to their wort. Both
Lallemand and Siebel Institute have a large market for their yeast food.
Lallemand sells over 200 tons of Fermaid K to one brewery.
Nitrogen is essential for the yeast to produce cell mass, DNA, RNA, ATP,ADP
and all of their metabolic enzymes. Nitrogen is also essential to protect
the yeast against alcohol toxicity near the end of fermentation. Nitrogen
and Amino acids also inter into the flavor producing components
Oxygen is an essential nutrient for a healthy yeast cell. As you know, yeast
can reproduce with oxygen(aerobic) and without oxygen (anaerobic).
However, a single yeast cell can reproduce about 21 times aerobically (it is
limited to about 21 times because that is all the room the yeast has on its
cell wall surface for new bud scars) and only about 3 - 5 times
anaerobically. Without oxygen, the yeast cannot produce lipids and sterols.
The lipids are growth factors and can quickly limit the growth cycle of each
yeast cell. Each mother cell shares 1/2 of her lipids with the daughter
cell, the daughter in turn shares her lipid with her daughter cell.
Depending on the amount of lipids in the original yeast cell, the
reproduction continues until there is not enough left for another
reproduction cycle. The lipids in the cell wall protect the yeast against
alcohol toxicity near the end of fermentation.
The beer maker can supply the yeast with the necessary lipids and sterols by
adding oleic acid and ergosterol or by adding 1, 2 or 3 saturation's of
oxygen (8, 16 or 24 ppm O2).
There should be no concern regarding the sterols. All of nature produces
sterols. They are integral structural components of yeast cells membranes
and are essential in the maintenance of plasma membrane permeability. Humans
have a similar system. When it is deficient, the cell wall becomes tough
and leathery and nutrients cannot pass into the yeast cell and alcohol
cannot pass back out of the yeast. It is easy to get steroids and sterols
mixed up. All sterols are steroids but not all steroids are sterols. Some of
the steroids in humans are the male and female sex hormones. The chief
sterol in yeast is ergosterol, which is the precursor of vitamin D.. Sun
rays on ergosterol produced vitamin D.
For your interest, some breweries produce beer in very large fermenters that
require several batches of wort to fill them. They will prepare the first
batch of wort, aerate it on the way to the fermenter and add the yeast.
They will prepare another batch of wort, aerate it and pump on top of the
first batch. This is repeated one or two more times. For those that are
afraid to add air or oxygen later in the fermentation can take some comfort
from this process in which air is added several times.
The lipids produced in the yeast cell should present no problem in the beer
head properties.
Figure 5 represents two wort fermentations. One of the wort was 100 malt.
The other wort was single strength malt wort and a cereal adjunct (probably
corn or rice) syrup that brought the soluble solids up to about 28 % equal
to the malt wort. For all practical purposes it shows that adequate oxygen
can replace ergosterol and that cereal adjunct can ferment equally as well
as 100% malt if adequate nitrogen is supplemented.
I have sponsored research at the U. of C. Davis brewing school that
indicates that a satisfactory beer can be made with up to 75% cereal
adjunct and 25% malt wort when supplemented with adequate amounts of Fermaid
K.
Yeast extract can be an excellent source of nutrient for beer making. 100%
yeast extract might impart a slight yeasty note to the beer. A balance of
yeast extract Fermaid 60 and Fermaid K would be an excellent combination.
It is easy to calculate the amount on nitrogen required . We can work on
that as needed.
Subsequent research has shown that adding nitrogen several times throughout
the fermentation levels off the fermentation rate. There is no sudden burst
in the rate at the beginning then a rapid decline. The rate will remain
level until the end of the fermentation.
Re. The hexokinase comment. Beer yeast's are glucose inhibited. This means
that they will not ferment maltose while they are utilizing the glucose.
They will utilize the sugars in the wort in the order of their size;
glucose, fructose, sucrose ,maltose ,maltotriose then maybe maltotetrose. I
am not sure if the fermentation rate would be speeded up if the yeast could
tackle all of the sugars at once. There is some work being done by research
labs to develop a yeast that is not glucose inhibited.
The Sake yeasts that I have worked with are sugar intolerant. High levels
of sugar have toxic effect on the yeast. They respond very well to the slow
addition of sugar into their media. The Koji amylase enzyme does just that.
This principle can definitely be applied to any fermenting material. I over
see the production of millions of gallons of product this way world wide.
High levels of nutrients and oxygen are required. I am not sure if the yeast
is accommodated to higher levels of alcohol by the slow introduction of
sugar (could very well be) or does this method minimize the combined toxic
effect of both alcohol and sugar.
For anyone interested we can work with them.
Lallemand has kits in the Scandinavian countries that will produce 20 -21%
alcohol in less that a week. So it can be done.
I think that it would be fun for the home beer maker to play with gravity,
nutrients and Oxygen.
Clayton Cone
Cheers!
Jethro Gump
Rob Moline
brewer at isunet.net
Lallemand Web Site consultant
jethro at isunet.net
"The More I Know About Beer, The More I Realize I Need To Know More About
Beer!"
Return to table of contents
Date: Mon, 22 Feb 1999 22:48:40 -0500
From: birman at netaxs.com
Subject: Philly Competition March 20, 1999
Hear ye, hear ye Homebrewers of Philly & Suburbs is having their annual
Best of Philly and Suburbs Competition. March 20,1999
Details at:
http://www.netaxs.com/~shady/hops/
Entries due 3/11
Judges/stewards contact Joe at birman at netaxs.com
thanks
Joe
Return to table of contents
Date: Mon, 22 Feb 1999 20:53:20 -0700
From: Doug Roberts <gertchie at earthlink.net>
Subject: Automatic Mill, was Re: Motors for Malt Mill
Ok, I'm happy now. I received an Automatic Mill from William's Brewing
for Christmas, and I was _not_ happy with how it performed. It had
problems milling the larger Marris Otter 140 L crystal. I sent it back
and received another in exchange (Williams is a good company: no muss,
no fuss). Last weekend I used it to mill 26# of Hugh Baird Marris
Otter for a 10-gal batch of special bitter. Milled all 26# in 15
minutes with the DeWalt 3/8 drill turning the shaft. Nice even crush.
Automatic must have had some problems reported with early versions of
the home brew model. I noticed that the rollers have a different cut
on them than the first one I had.
Bottom line: I recommend the Automatic Mill. It's bullet-proof, fast,
and does a nice job. The sintered-brass bushings & steel construction
will guarantee a long happy life.
- --Doug
gertchie at earthlink.net
Return to table of contents
Date: Mon, 22 Feb 1999 23:00:37 -0500
From: Alan McKay <amckay at ottawa.com>
Subject: This is gyle!
I just did a search in the archives on "gyle AND priming" and
couldn't really come up with a definitive formula to compute
the amount required. I found these 3 :
http://hbd.org/hbd/archive/1573.html#1573-25http://hbd.org/hbd/archive/1350.html#1350-16http://hbd.org/hbd/archive/1349.html#1349-3
And the newest of those is a couple of years old.
I'm doing the search for some folks in one of the German forums.
(I'll leave the play on words in the subject line to your
imagination :-))
So, what's the formula that's commonly accepted nowadays?
(Preferably in metric ;-))
thanks,
-Alan
- --
"Brewers make wort, yeast makes beer"
- Dave Miller's Homebrewing Guide
http://www.magma.ca/~bodnsatz/brew/tips/Return to table of contents
Date: Mon, 22 Feb 1999 23:34:00 -0500
From: John Herman <johnvic at earthlink.net>
Subject: small bottles?
Any ideas on where to buy small bottles? I guess I could buy a case of
Malta and dump it.
Thanks
- --
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
* Bicycling, Bassing and Brewing *
* *
* The Real 3 B's! *
* *
* John Herman *
* johnvic at earthlink.net *
//////////////////////////////////
Return to table of contents
Date: Mon, 22 Feb 1999 21:50:33 -0800
From: Jack Schmidling <arf at mc.net>
Subject: Milling Grains
Dan Listermann <72723.1707 at compuserve.com>
"The other week Jack Schmidling posted the following:
< If you look at the oft published drawing of a six roller
> mill.....
Just to keep the record straight, I posted no such thing. It was
the sales manager for that Canadian company who always seems to be
trying to pick a fight. He got nowhere on r.c.b so he lifted that
from my web page and came trolling here in the HBD and now seems
to have gotten a bite.
"I tried to reproduce the claims made by Jack's promotional
material with an adjustable Maltmill.
Again for the record, that statement was paraphrased from a report
submitted by George Fix after an evaluation of one of the first
MM's ever shipped. The data is NOT paraphrased, it is his data.
Because of your difficulty in reproducing the results, I sent samples
to Sieble Institute along with samples from your mill and the results
more or less corroborate the fact that the MM provides "about the
same distrubution" and I went away satisfied. I did nothing with the
data provided on the grist from your mill other than give a sigh of
satisfaction. However, as one can make anything one wants with
an adjustable mill, the results didn't seem worth publishing. I
was more interested in what our mill did.
"I have not found the data that Jack publishes to be remotely
reproducible even with multiple passes and adjustments between passes.
I take no responsibility for your problems in reproducing the results.
"Someone (?) will point out that I am not without interests here and they
are right. I am willing to lend my seives to others who might want to
attempt to reproduce Jack's claims. It is kinda fun! Just ask.
It certainly is a good exercise and if everyone understood the basics
of the testing, it would make life much simpler for all of us who
make mills. I wish I had a buck for everyone who complained that
there was "too much flour in the grist from my brand new mill".
Because they do not understand the technology, they assume that
all fine grist is evil. When asked how much is too much, they haven't
a clue.
BTW, Sieble uses a motorized and timed shaker so I would not be
surprised if someone got different results hand shaking the sieves.
js
- --
Visit our WEB pages: http://user.mc.net/arf
ASTROPHOTO OF THE WEEK..... New Every Monday
Return to table of contents
Date: Mon, 22 Feb 1999 22:41:37 -0700
From: Paul Dey <alldey at uswest.net>
Subject: iodophor film
In 2960, Jethro mentions, among other good info and in reference to a
brown iodophor film:
>>>>>BTW, I still see this problem occasionally, even with other
manufacturers Iodophor, and have still not yet identified the problem,
though I tend to believe that introducing the Iodophor into solution
slowly has a beneficial effect, but this does not seem to be universally
true.)<<<<<<
I too have seen the film and its been mentioned in the past on this
forum though I don't recall any explanations. I especially notice
formation if I'm filling iodophor-laden carboys with a spray nozzle set
to high pressure. From that, I've assumed that the film consists of an
ozide of iodine. Chemists?
Return to table of contents
Date: Tue, 23 Feb 1999 07:25:40 -0500
From: "Fred L. Johnson" <FLJohnson at worldnet.att.net>
Subject: Lautering Temperature
My system includes separate mash and lauter tuns. I typically mashout at
168 F for 10 minutes, transfer to the lauter tun, recirculate for about 10
minutes until almost crystal clear, and then sparge. During the
recirculation, I am losing heat quickly, despite the fact that my lauter
tun
is insulated. Most of this heat loss is probably occurring in the grant
and
during the manual transfer back to the lauter tun. The top of my grain bed
may easily drop to 145 F, perhaps even lower. The sparge water may also
have dropped some so that the sparge may only be at 150-155 F. Finally, I
can't heat my kettle until after the sparge and I have no idea how low the
temperature has gotten on the wort.
I have not been concerned about this until recently when I was reading
Steve
Alexander's warning against the dangers of low temperatures during
the mash. He points out that mashout (at 168-170 F) does NOT denature all
the enzymes,
which sets up my question and fears that post-mashout, pre-boil
temperatures
may be affecting head retention, etc. I have sometimes been disappointed
with head retention on some of my beers, but I have never before considered
the
temperature of the wort following mashout as a potential source of the
problem.
To Steve Alexander (et al. ): I would appreciate some more discussion on
this issue. Do I need to take further measures to insure that my wort does
not drop too low during the sparge and before the boil?
- --
Fred L. Johnson
Apex, North Carolina
USA
Return to table of contents
Date: Tue, 23 Feb 1999 08:30:48 -0500 (EST)
From: Paul Shick <SHICK at JCVAXA.jcu.edu>
Subject: Re: Fake decoction/ Weissheimer haze ?
Hello all,
Scott Moore asks about ways to get decoction-type malt
flavor without the hassle (and protein rest risks.) Lately I've
been trying to do this using about 5-10% DeWolf-Cosyns Aromatic
malt in the grist. This malt has a lot of the melanoidin content
that you get from decoctions, although no doubt in very different
form. In particular, this has worked well with very malty styles
like Oktoberfests and bocks (at least from initial tasting in the
bocks.) I don't get quite the same level of maltiness in a German
Pilsener from a 5% charge, but that might be due to the lower
saccharification temperature and dryer finish. So far, it seems
to be doing the trick.
Mike Maceyka comments on his haze problems with Weissheimer
malts. My experiences have been quite different, although I was
initially worried about the Weissheimer malts, because the specs
available on their web page (and the 97 HBD) seemed right on the edge
of needing a protein rest. In particular, the Kolbach index was in
the high 30s, much lower than I was comfortable with a single infusion.
However, several very accomplished brewers answered my HBD questions
with a wealth of detail, but different suggestions, ranging from
single infusion to 4 temperature regimes. I eventually decided to try
a single infusion and not to look too closely at the haze, if it
occured. The resulting 10 gallons of German Pilsener is clear enough to
read through. It was mashed at 152F for 30 minutes, with recirculation
and gentle heating to 158 over 25 minutes, then raised to 164 for runoff.
A dunkelbock on the dregs of one carboy of the Pilsener was very clear
when racked to the secondary at 3 weeks. (Tastes great too. The
aromatic malt and tons of Weissheimer Munich really worked well.) A
Maibock on the other dregs was cloudy when racked at 2 weeks, but is
clearing nicely at 4 weeks. I'm really happy with these Weissheimer
malts! Maybe I'm just getting better at keeping track of pH, etc., as
far as the clarity goes, but the flavor is at least is nice as any
European malt I've tried.
Paul Shick
Basement brewing in Cleveland Hts OH
Return to table of contents
Date: Tue, 23 Feb 1999 09:49:59 -0500
From: "Peter J. Calinski" <PCalinski at iname.com>
Subject: Re: Computer Controlled Brewing
My son sent me the following email this AM (2/23/99).
- --------------------------------------------------------------
Dad:
This month (February 1999) in PRODUCT DESIGN AND DEVELOPMENT.
www.pddnet.com
They have an article on PC-based automation of "critical processes" in
brewing
at the Spoetzl Brewery.
The web site talks more about it if you can't get the edition.
I just got it. Tonight I'll take it home and read it and save it for you.
Joe
- ---------------------------------------------------------------
It will be a few days before I can checkout the www. but I thought it may
be of interest to the group.
Pete Calinski
East Amherst NY
Near Buffalo NY
0 Degrees 30.21 Min North, 4 Degrees 05.11 Min. East of Jeff Renner
Return to table of contents
Date: Tue, 23 Feb 1999 07:38:02 PST
From: chatgros at excite.com
Subject: Corny Keg Thread Size/Type
Auuggghhhh! Screech!!!
I want to close a third fitting (where a level sensor was inserted) on an
otherwise stock corny keg. It is the same threads that the in/out have. I
cannot find anything that fits the thread despit having bought examples of
most of caps in Home Depot. I do not ant to spend $7 for a 'fitting'.
Anyone know what the size/thread on corny fitting posts actually is?
Thanks.
_______________________________________________________
Get your free, private email at http://mail.excite.com/Return to table of contents
Date: Tue, 23 Feb 1999 10:33:31 -0600
From: "Formanek, Joe" <Jformanek at griffithlabs.com>
Subject: Drunk Monk Challenge - Second Notice!!
The Urban Knaves of Grain homebrew club is now accepting entries for
The 1st Annual DRUNK MONK CHALLENGE!!
This is an AHA/BJCP-sanctioned homebrew competition to be held March
6, 1999 at Founders Hill Brewery, Downers Grove, IL
This is the first event in the race for 1999 Midwest Homebrewer of the
Year.
Accepting all AHA categories of beer, mead, and cider, plus THE
MENACE OF THE MONASTERY, a special category for the best beer in a style
traditionally associated with monks: Belgian dubbel (2b), tripel
(2c), pale (2d), strong pale (2e), and strong dark (2f), and German
doppelbock(12c).
Entries: $5 each for 1-4 entries, $4 each for 5 or more entries.
Menace of the Monastery entries are $2 each (counted separately).
Two bottles required (just one for Menace), all the usual rules.
Judges needed! For judge/steward info, please contact Joe Formanek,
jformanek at griffithlabs.com, 630-378-4694 (H). For entry info,
contact Shane Coombs, srcoombs at synsysinc.com, 630-393-7303 (H), 630-820-5150
(W).
Even more info, including entry forms: see the Drunk Monk Challenge
website, http://www.synsysinc.com/srcoombs/ukgdmc.htm, or the UKG
website, http://ourworld.compuserve.com/homepages/stmckenna/ukg.html.Return to table of contents